Flys in my plants

So i bought some sticky traps a couple days ago and i checked them the same day i got the traps but i don’t know what these flys are or do to my plants. Would appreciate some help !

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Looks like fungal gnats. Fairly sime fix. Google fungal gnats treatments.


i already have the sticky traps so i guess i should be fine and just let me die on there own.

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Add a layer of sand ontop of your soil and they will die off faster.

They procreate in the moist soil


diatomaceous earth on top. peroxide water mix of 1 part peroxide and 3 parts water will kill eggs and larvae in the soil.


The yellow sticky cards a great for letting you know they are there and how large a population you have but do not affect the larvae from the eggs they lay in the top section of the soil. To combat those larvae which can munch on roots until they grow into adults you’ll want to treat with a product that contains BTi which is a bacteria that kills the larvae.
The adults eat the green growth on the top of soil that happens with watering too often without letting the top inch or so dry out between waterings.
I use this as well as a few other things. I don’t use Hydrogen peroxide as that can negatively affect my living soil critters too.

Sprinkle some on top of soil and water it in and the water wakes up the critters and they go to work looking for the fungus gnat larvae. They aren’t a huge issue if controlled but if not can be.


make sure not to overwater… let them dry out a bit and the knats will normally disappear… you will likely see them afain soon as their larve are likely already in the soil by now… keep things dryer and it will stop their life cycle from repeating… their larve cant survive in dry soil… mosquito dunk products also work pretty well against them… the sticky traps alone wont work


I use the mosquito bits as well if I ever see any fungus gnats, works great.

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BTi is the best cure. Available in mosquito bits, or a pure powder on ebay.

The yellow sticky cards will not eradicate them.

Try not to over water too often.

they just have these in my stores gonna have to order that if these don’t work.

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Or this spray

I couldn’t help you there. I don’t use bti. I kill the larvae with the peroxide mix and cover the top, and i mean cover lol, with diatomaceous earth. I also don’t water from the top until I see they are all gone. I pour water in my tray and the plant will literally suck it up into the pot.

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Those will work fine all you need to do is break them up into small sizes and water in as long as the package says BTi as the working ingredient it’s the same as I posted above just in a different form.

As far as the spray you linked below from Home Depot I wouldn’t use that at all but that’s just me and my health and my plants and soil critters health I don’t want to pollute…it is petroleum (oil) based.

Also the old “Trade Secret” bullshit so it can have anything they want in there and you’ll never know what it is.


This is what you need

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One thing that I use is increasing the airflow right at ground level. They don’t thrive very well in a constant breeze and will not stay there and reproduce. And of course peroxide is safe.

got you ill just buy the first ones then i need them asap

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HP is safe if you aren’t worried about it negatively affecting your soil microbes. There is the cheap HP at the stores that contain a preservative and then there is the food grade HP without that stuff.
In order to reach the larvae in the soil you’ll have to drench the soil with the HP mix and it will kill the good the bad and the ugly.
There are differing opinions one can find and read about on the web but as I understand things it will harm critters.
I’ve used it for top of plant as a spray with food grade mix and that’s fine and I’ve used it with soil a soil drench…if you do that you’ll want to reintroduce more soil critters with a aerated compost tea.
If your growing in hydro I don’t have any experience with that but have read people that use it to clean roots due to molds growing etc.
Living soil if that’s what one is using will be negatively affected with using it.

Feel free to correct me as I’m always will to listen and learn

And as mentioned by others above using sand or DE can help by keeping the adults from getting to their food source (green algae etc) growing on the top and keeps them from getting into the soil to reproduce

A good read on using HP…many articles out there some say go for it others not.

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You are correct that I should clarify it will kill everything in the soil including your roots if you mix it too strong


just bought the dunks i showed but doesn’t say how long to leave in water.

I haven’t used the dunks but only the granules shown in my post above but I’m sure if you crush a couple up into small pieces and then apply to top soil and then when you water them it will activate the BTi
May also consider scratching the broken pieces into the top inch or 2 of soil like you would using a dry nutrient amendment and water.
I also thing those “dunks” are used in standing water etc and are just tossed whole into it. But that’s not what your needing it for.
I have seen where it is plopped in water and then used but I don’t have any experience doing it that way…
The water will rehydrate and bring alive the BTi and they will do their thing regardless of application method. I would soak for a least a couple hours

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